Actuators for Soft Robotics

Abstract

Although we do not know as yet how robots of the future will look like exactly, most of us are sure that they will not resemble the heavy, bulky, rigid machines dangerously moving around in old-fashioned industrial automation. There is a growing consensus, in the research community as well as in expectations from the public, that robots of the next generation will be physically compliant and adaptable machines, closely interacting with humans and moving safely, smoothly and efficiently – in other terms, robots will be soft.

This chapter discusses the design, modeling and control of actuators for the new generation of soft robots, which can replace conventional actuators in applications where rigidity is not the first and foremost concern in performance. The chapter focuses on the technology, modeling, and control of lumped parameters of soft robotics, that is, systems of discrete, interconnected, and compliant elements. Distributed parameters, snake-like and continuum soft robotics, are presented in Chap. 20, while Chap. 23 discusses in detail the biomimetic motivations that are often behind soft robotics.

AA

agonist–antagonist

AMASC

actuator with mechanically adjustable series compliance

CMCs

ceramic matrix composite

CNT

carbon nanotube

CVT

continuous variable transmission

DOF

degree of freedom

EAP

electroactive polymer

ECD

eddy current damper

ER

electrorheological

FD

friction damper

ILQR

iterative linear quadratic regulator

IPMC

ionic polymer-metal composite

KERS

kinetic energy recovery system

LQR

linear quadratic regulator

LWR

light-weight robot

MACCEPA

mechanically adjustable compliance and controllable equilibrium position actuator

MEMS

microelectromechanical system

MIA

mechanical impedance adjuster

MMC

metal matrix composite

MR

magnetorheological

NMMI

natural machine motion initiative

OC

optimal control

ODE

ordinary differential equation

PAM

pneumatic artificial muscle

PANi

polyaniline

PLZT

lead lanthanum zirconate titanate

PMC

polymer matrix composite

PPy

polypyrrole

PVDF

polyvinylidene fluoride

PZT

lead zirconate titanate

SEA

series elastic actuator

SMA

shape memory alloy

SMP

shape memory polymer

TCP

tool center point

VIA

variable impedance actuator

VS-Joint

variable stiffness joint

VSA

variable stiffness actuator

WAM

whole-arm manipulator

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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.DLR Institute of Robotics and MechatronicsWesslingGermany
  2. 2.Interdepartmental Research Center “E. Piaggio”University of PisaPisaItaly

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